【作者】 李鑫；

【导师】 刘丽芳；

【作者基本信息】 东华大学 ， 纺织科学与工程， 2021， 硕士

【摘要】 纳米二氧化钛是应用最广泛的光触媒材料,在纺织、医疗、环境领域中发挥着重要作用。将纺织品与纳米二氧化钛复合,可以制备具有抗菌、防紫外、自清洁等功能纺织品。但纳米二氧化钛一旦从纺织品中脱落,就会通过多种途径进入人体,并随血液循环系统传输到各个组织器官,危害人体健康。目前国内没有关于光触媒纺织品安全评价标准,因此建立纳米二氧化钛织物可萃取纳米二氧化钛含量以及安全性评价方法极为重要。本论文通过添加分散剂制备分散性好的纳米二氧化钛分散液,通过浸轧法将其负载到棉织物表面,得到光触媒织物,通过对织物上纳米二氧化钛脱落量进行测定分析,结合细胞毒性实验,对纳米二氧化钛毒性进行评价。建立纳米二氧化钛光触媒纺织品安全性评价方法,形成团体标准草案,填补相关检测标准的空白。主要研究内容和结果如下:采用六偏磷酸钠作为分散剂,探究分散剂用量及pH对纳米二氧化钛水溶液分散效果的影响。通过沉降实验、Zeta电位、粒径测试等方法来表征,确定最优分散条件。之后通过浸轧法制备纳米二氧化钛光触媒织物,探究纳米二氧化钛浓度对织物光催化性能影响。结果表明当分散剂用量为纳米二氧化钛质量5%,pH为9时,纳米二氧化钛水溶液分散性能最好,此时纳米二氧化钛水合粒径为143.2nm。织物对亚甲基蓝降解实验说明,随整理液中纳米二氧化钛浓度的增加,织物光催化性能逐渐增大,但过高的浓度对光催化性能提升作用较小。最后确定纳米二氧化钛整理剂浓度为2g/L,此时在紫外灯照射下,织物对亚甲基蓝降解率为49.9%。通过恒温水浴振荡对织物中纳米二氧化钛进行萃取来模拟织物在穿着过程中纳米二氧化钛脱落情况。探究温度、时间、频率、萃取介质对纳米二氧化钛萃取的影响。采用电感耦合等离子体光谱仪(ICP-OES)对消解后萃取液中纳米二氧化钛含量进行测定。结果表明,纳米二氧化钛萃取量受萃取介质和频率的影响较大,受温度、时间的影响较小。结合国内目前纺织品检测标准,确定了萃取实验条件,即萃取介质为酸性汗液、萃取时间为60min、萃取温度为37℃、振荡频率为60r/min。通过ICP-OES对纳米二氧化钛含量进行测定,此方法具有较好的灵敏度和准确性。使用该方法对市售的两种以及自制的一种光催化织物进行检测,发现纳米二氧化钛会发生一定程度脱落,最高脱落量为0.37mg/g,对人体健康具有潜在危害。通过细胞毒性实验,从细胞存活率、细胞凋亡、细胞形态三方面来表征纳米二氧化钛毒性,探讨了纳米二氧化钛粒径、浓度对其毒性的影响。结果表明,纳米二氧化钛毒性具有明显的时间依赖性,细胞在暴露24h后并没有引发大量死亡,但细胞凋亡比例增加,随着时间的增加,细胞死亡率明显提高,72h后表显出明显毒性,粒径对细胞的毒性并没有单一的规律,40nm二氧化钛毒性大于25nm、60nm。浓度对毒性的影响整体上随浓度增加而增加,在100μg/ml浓度40nm二氧化钛暴露72h下细胞存活率为77%。最终建议织物中25nm二氧化钛萃取量在10～100μg/ml之间,40nm二氧化钛萃取量在200μg/ml以内。更多还原

【Abstract】 Nano-titanium dioxide is the most widely used photocatalyst material and plays an important role in textile,medical and environmental fields.Combining textiles with nano-titanium dioxide can prepare textiles with functions such as antibacterial,anti-ultraviolet,and self-cleaning.However,once nano-titanium dioxide falls off from textiles,it will enter the human body through various ways,and will be transported to various tissues and organs with the blood circulatory system,endangering human health.At present,there is no safety evaluation standard for photocatalyst textiles in China,so it is extremely important to establish the extractable nano-titanium dioxide content of nano-titanium dioxide fabrics and the safety evaluation method.In this paper,nano-TiO₂ dispersion liquid with good dispersibility was prepared by adding dispersant,and it was loaded on the surface of cotton fabric by padding method to obtain photocatalyst fabric.The toxicity of nano-titanium dioxide was evaluated.Establish a safety evaluation method for nano-titanium dioxide photocatalyst textiles,form a draft group standard,and fill in the blank of relevant testing standards.The main research contents and results are as follows:Using sodium hexametaphosphate as dispersant,the effect of dispersant dosage and pH on the dispersion effect of nano-titania aqueous solution was investigated.Characterized by sedimentation experiment,Zeta potential,particle size test and other methods to determine the optimal dispersion conditions.Then,nano-titania photocatalyst fabrics were prepared by padding method,and the effect of nano-titania concentration on the photocatalytic performance of fabrics was explored.The results show that when the amount of dispersant is 5%by mass of nano-titanium dioxide and the pH is 9,the dispersion performance of nano-titanium dioxide aqueous solution is the best.At this time,the hydrated particle size of nano-titanium dioxide is 143.2 nm.The degradation experiment of methylene blue on the fabric showed that with the increase of the nano-titanium dioxide concentration in the finishing solution,the photocatalytic performance of the fabric gradually increased,but the too high concentration had little effect on the improvement of the photocatalytic performance.Finally,the concentration of nano-titanium dioxide finishing agent was determined to be 2g/L.At this time,under the irradiation of ultraviolet lamp,the degradation rate of methylene blue on the fabric was 49.9%.The extraction of titanium dioxide in fabrics was performed by constant temperature water bath shaking to simulate titanium dioxide shedding during the wearing process of fabrics.The effects of temperature,time,frequency,and extraction medium on the extraction of titanium dioxide were explored.The titanium dioxide content of the extracted solution was measured by inductively coupled plasma spectrometry（ICP-OES）after ablation.The results showed that the amount of titanium dioxide extraction was more influenced by the extraction medium and frequency,and less influenced by the temperature and time.Combined with the current domestic textile testing standards,the extraction experiment conditions were determined,that is,the extraction medium is acid sweat,the extraction time is 60min,the extraction temperature is 37℃,and the oscillation frequency is 60r/min.The ICP-OES is used to determine the content of nanometer titanium dioxide.This method has good sensitivity and accuracy.Using this method to detect two kinds of commercially available photocatalytic fabrics and one self-made photocatalytic fabric,it was found that the nanometer titanium dioxide will fall off to a certain extent,with the highest fall off amount of 0.37mg/g,which is potentially harmful to human health.Through the cytotoxicity experiment,the toxicity of nanometer titanium dioxide was characterized from three aspects:cell survival rate,cell apoptosis and cell morphology,and the influence of nanometer titanium dioxide particle size and concentration on its toxicity was discussed.The results show that the toxicity of nano-titanium dioxide is obviously time-dependent.The cells did not cause a large number of deaths after 24 hours of exposure,but the proportion of cell apoptosis increased.With the increase of time,the cell death rate increased significantly,and it showed obvious toxicity after 72 hours.There is no single rule for the toxicity of particle size to cells.The toxicity of 40nm titanium dioxide is greater than25nm and 60nm.The effect of concentration on toxicity increases as the concentration increases.The cell survival rate is 77%after 72h exposure of 40nm titanium dioxide at a concentration of 100μg/ml.Finally,it is suggested that the extraction amount of 25nm titanium dioxide in the fabric is between 10 and 100μg/ml,and the extraction amount of40nm titanium dioxide is within 200μg/ml.更多还原